I hit 39 almost 40. Crazy dense long hair, zero issues.
I had a true Telogen Effluvium before any medication. Most likely Thyroid related. I was thinning gradually, still freaking out, but in retrospect went from no loss to 20-50 hairs a day.
A year in a ‘top’ derm told me to add Minoxidil and that it could do no harm. She also said at the time that I had no male pattern baldness.
I started May 2017, I swear I’m 3 weeks I shed half of my hair which was noticeable and painful as they wear all thick long black hairs. Shedding continued, some regrowth but weak thin hair that never fully matured.
A year later I added Finasteride. Still shedding with no clue if the Finasteride helped or if the miniaturization versus minoxidil shed was a losing battle. Either way.
If I had to do it again I would have waited to stabilize the loss before thinking about Minoxidil. I think it has truly messed up my hair cycles everywhere.